Massingale worked at the company’s P-1 mine in Harlan County. A grand jury charged the company and three officials with exposing miners to the risk of injury or death by violating safety rules in June 2011.

Massingale is the only one who is pleading guilty: the company and two other officials have pleaded not guilty.

An attorney for Manalapan Mining Co. entered a guilty plea for the company on a charge that it had miners use equipment that did not have canopies or cabs to protect them if sections of the roof or walls fell.

The company could be fined as much as $250,000.

Jefferson Davis, who was operations manager at the company’s mine, and Joseph Miniard Jr., who was the superintendent, each pleaded guilty to a similar misdemeanor charge punishable by up to a year in jail.

Miniard also pleaded guilty to a felony charge that he signed off on inspection reports that failed to note hazardous conditions in the underground mine.